Centrifugal separator having valve in passageway beneath distributor foot

ABSTRACT

A centrifugal separator having discharge passageways at the drum periphery for intermittent discharge of solids and a piston valve for opening and closing of the discharge passageways. A distributor receives the separator feed, conveys the feed along the drum axis, and then radially outward through a radially extending passageway defined by the distributor foot and the piston valve. Openings are provided in the distributor foot adjacent the axis for passage of the feed upwardly to the stack of separator plates overlying the distributor foot. A valve plate is mounted either on the piston valve or the distributor foot and extends either toward the distributor foot or toward the piston valve for engagement therewith to close the radially extending passageway at a location radially outwardly of the openings in the distributor foot, with the piston valve in the closed position, and open the radially extending passageway with the piston valve in the open position. The valve in the radially extending passageway prevents feed from by-passing the separator plates during the normal centrifuging operation.

United States Patent Niemeyer CENTRIFUGAL SEPARATOR HAVlNG VALVE IN PASSAGEWAY BENEATH DISTRIBUTOR FOOT Heinrich Niemeyer. Oelde, Germany Westfalia Separator AG, Oelde- Westfalen, Germany Filed: Mar. 15. 1974 Appl. No.: 452,243

inventor:

Assignee:

Foreign Application Priority Data Mar. 20. 1973 Germany 23l3669 References Cited UNITED STATES PATENTS 8/1973 Bruning 233/20 A [/1974 Stroucken i. 233/20 A Prinuu-y [:lruminer-George H. Krizmanich Attorney, Agent, or Firm-Burgess. Dinklage & Sprung Mar. 18, 1975 [57] ABSTRACT A centrifugal separator having discharge passageways at the drum periphery for intermittent discharge of solids and a piston valve for opening and closing of the discharge passageways. A distributor receives the separator feed. conveys the feed along the drum axis. and then radially outward through a radially extending passageway defined by the distributor foot and the piston valve. Openings are provided in the distributor foot adjacent the axis for passage of the feed upwardly to the stack of separator plates overlying the distributor foot. A valve plate is mounted either on the piston valve or the distributor foot and extends either toward the distributor foot or toward the piston valve for engagement therewith to close the radially extending passageway at a location radially outwardly of the openings in the distributor foot, with the piston valve in the closed position, and open the radially extending passageway with the piston valve in the open position. The valve in the radially extending passageway prevents feed from by-passing the separator plates during the normal centrifuging operation.

5 Claims, 1 Drawing Figure BACKGROUND The invention relates to a self-cleaning centrifugal separator having a distributor terminating in a distributor foot having apertures which connect the distributor entrance chamber with the separating chamber, and in which the entrance chamber communicates with the solids chamber of the drum through an annular gap between the distributor foot and the piston valve.

Such a drum is known, for example, from German Pat. No. l,297,036.

The coarser solids, which separate from the liquid right in the entrance chamber, pass through the abovementioned annular gap into the solids chamber outside of the plate stack. This preliminary separation, which takes place automatically, is very advantageous because the solids running from the entrance chamber directly into the solids chamber do not load the plate stack. It is disadvantageous, however, that a portion of the incoming liquid mixture also passes through this annular gap into the space outside of the plate stack from which the specifically heavier fluid component flows to its outlet. The greater the percentage of the specifically heavier component is, the greater this flow will be. At high throughputs, therefore, it is inevitable that, due to the constant mixing with a portion of the incoming fluid, a portionthough a small one-of the specifically lighter component is carried out together with the specifically heavier liquid component. This is very disadvantageous in the separation of milk, for example.

For the purpose of largely preventing this mixing, centrifugal separators of older design have been constructed so that, when the distributor was inserted, the distributor foot was guided on an annular projection of the drum bottom until it was seated and formed with the drum bottom a closed preliminary separation chamber. A closed chamber, however, has the disadvantage that it is rapidly filled with solids, especially when the rising channels are located far out and the fluid being separated contains relatively large amounts of solids. A centrifugal separator of this kind is shown by German Pat. No. 368,2 l3, for example.

It is also in the prior art to connect the preliminary separation chamber and the solids chamber of the drum together through permanently open passages uni formly distributed over the periphery of the distributor foot. This brings it about that, on the one hand, the solids separating from the fluid as soon as they enter, pass into the solids chamber during operation, while on the other hand the flow of fluid is less than it would be in comparison to a permanently open annular gap. A drum of this kind is shown, for example, in German Pat. No. 416,528.

THE INVENTION The invention is addressed to the problem of constructing a self-cleaning centrifugal separator of the kind described in the beginning so that the preliminary separation chamber formed by the distributor foot and piston valve will be closed during the centrifuging periods and open during the ejection of the solids.

The invention is characterized by a valve plate fastened to the piston valve and a projection provided on the distributor foot outside of the apertures passing through the foot, the said projection cooperating with the cylindrical outer surface of the valve plate to open and close the preliminary separation chamber upon the axial movements of the piston valve.

In the operation of the drum of the invention, the preliminary separation chamber is also emptied each time that the solids are ejected. The solids which deposit in the preliminary separation chamber provide an adequate seal. Since an absolute sealing of this chamber is not important, there is no need for special seals.

Thus, the invention is concerned with a centrifugal separator having a rotatably mounted drum defined by an upper end member and a lower end member, enclosing a drum chamber for the separation. The separator has at least one discharge passageway disposed at the radially outward periphery of the drum. A piston valve is disposed within the drum and defines one of the end members, and is movable vertically to open and close the discharge passageway or passageways. A distributor is disposed coaxially within the drum for receiving feed to the separator and conveying the feed along the axis of the separator. The distributor has a distributor foot extending radially outwardly from adjacent the drum axis and over at least a portion of the piston valve, defining with the piston valve a radially extending passageway for receiving drum feed. The distributor foot terminates at the radially outwardly disposed end thereof in spaced relation with the piston valve so as to define an annular gap between the piston valve and distributor foot communicating the radially extending passageway with the drum chamber. The distributor foot has an opening or openings adjacent the drum axis for passage of the feed from the distributor to the drum chamber. According to the invention, a valve plate is mounted either on the piston valve or the distributor foot and extends either towards the distributor foot or toward the piston valve for engagement therewith to close the radially extending passageway at a location radially outwardly of the opening or openings in the distributor foot, with the piston valve in the closed position and open the radially extending passageway with the piston valve in the open position.

Means are provided for separating the feed to the separator, such means being disposed within the drum chamber adjacent the drum axis. Thus a stack of separator plates are disposed over the distributor foot. The separator plates provide a separating section or chamber for radially inward flow of specifically lighter component of the feed and radially outward flow of specifically heavier componet. There is also provided a dis charge passageway for receiving the specifically heavier component and discharging it from the drum.

THE DRAWING An embodiment ofthe invention is represented in the drawing.

Referring to the drawing, a rotatably mounted separator drum includes upper end member 18 and bottom 19 which are secured together by ring 20. The drum includes discharge passageway 3 for intermittent discharge of solids. Piston valve 1 is disposed within the bottom 19. The piston valve 1 and the upper end member 18 together define a drum chamber 24 for the separation of the liquid mixture and the solids. The drum chamber includes separating section or chamber 8 in which a stack of separator plates 14 is mounted, and solids collection section or chamber 13. Distributor 4 is disposed coaxially within the drum, and includes distributor foot 5, having an opening 6 for introduction of feed into the separating section or chamber 8. The pis' ton valve 1 is movable axially to open and close discharge passage 3.

The piston valve 1 is placed in the closed position represented in the drawing when the closing chamber 2 is filled with a control fluid, and when the control fluid is let out of this chamber. by introducing fluid into passageway 21 to actuate control fluid relief valve 22, the piston valve is moved by the pressure of the drum charge into its open position. In the open position it releases the annular gap 3 for the ejection of the solids separated from the liquid.

The distributor 4 is provided with conical distributor foot 5. Openings or apertures 6 in the distributor foot connect the entrance chamber 7 with the separating chamber 8. Between the distributor foot and the piston valve 1 there is a radially extending passageway 23 terminating in a permanently open annular gap 9.

In accordance with the invention, a valve plate 10 is fastened to the piston valve, the cylindrical outer surface of said valve plate cooperating with a projection I] provided on the distributor foot 5, the projection being machined at a greater distance from the axis of rotation than the apertures 6 in the distributor foot. In the closed position of the piston valve l, the preliminary separation chamber l2 is closed off from the solids chamber 13 outside of the plate stack 14, and in the open position it is connected thereto through an annular gap forming at 15.

With the drum design of the invention it is impossible. on the one hand, for a portion of the incoming liquid mixture to flow during the centrifuging periods into chamber 13 from which the specifically heavier liquid component is flowing out through discharge passageway 16. and on the other hand the periodical opening of the preliminary separation chamber [2 prevents overfilling with solids.

What is claimed is:

1. In a centrifugal separator comprising:

a. a rotatably mounted drum having an upper end member and a lower end member enclosing a drum chamber for the separation, and having at least one discharge passageway disposed at the radially outward periphery of the drum,

b. a piston valve disposed within the drum defining one side of the drum chamber and movable vertically to open and close the discharge passageway(s),

c. a distributor coaxial within the drum for receiving feed to the separator and conveying the feed along the axis of the separator, the distributor having a distributor foot extending radially outwardly from adjacent the drum axis and over at least a portion of the piston valve and terminating at the radially outwardly disposed end thereof in spaced relation with the piston valve so as to define an annular gap between the piston valve and distributor foot communicating the radially extending passageway with the drum chamber,

d. at least one opening in the distributor foot adjacent the drum axis for passage of the feed from the distributor to the drum chamber,

the improvement which comprises:

e. a valve plate mounted either on the piston valve or the distributor foot and extending either toward the distributor foot or toward the piston valve for engagement therewith to close the radially extending passageway at a location radially outwardly of said opening(s) in the distributor foot, with the piston valve in the closed position and open the radially extending passageway with the piston valve in the open position.

2. Centrifugal separator according to claim 1, the

valve plate being mounted on the piston valve.

3. Centrifugal separator according to claim 2, and a projection on the distributor foot for cooperation with the valve plate for said engagement.

4. Centrifugal separator according to claim 1, means for separating the feed to the separator disposed within the drum chamber adjacent the drum axis. for radially inward flow of a specifically lighter component of the feed and radially outward flow of a specifically heavier component, the drum including a discharge passageway for receiving at least part of said specifically heavier component and discharging it from the drum.

5. Centrifugal separator according to claim l, the lower side of the drum chamber being defined by the piston valve.

i i l 

1. In a centrifugal separator comprising: a. a rotatably mounted drum having an upper end member and a lower end member enclosing a drum chamber for the separation, and having at least one discharge passageway disposed at the radially outward periphery of the drum, b. a piston valve disposed within the drum defining one side of the drum chamber and movable vertically to open and close the discharge passageway(s), c. a distributor coaxial within the drum for receiving feed to the separator and conveying the feed along the axis of the separator, the distributor having a distributor foot extending radially outwardly from adjacent the drum axis and over at least a portion of the piston valve and terminating at the radially outwardly disposed end thereof in spaced relation with the piston valve so as to define an annular gap between the piston valve and distributor foot communicating the radially extending passageway with the drum chamber, d. at least one opening in the distributor foot adjacent the drum axis for passage of the feed from the distributor to the drum chamber, the improvement which comprises: e. a valve plate mounted either on the piston valve or the distributor foot and extending either toward the distributor foot or toward the piston valve for engagement therewith to close the radially extending passageway at a location radially outwardly of said opening(s) in the distributor foot, with the piston valve in the closed position and open the radially extending passageway with the piston valve in the open position.
 2. Centrifugal separator according to claim 1, the valve plate being mounted on the piston valve.
 3. Centrifugal Separator according to claim 2, and a projection on the distributor foot for cooperation with the valve plate for said engagement.
 4. Centrifugal separator according to claim 1, means for separating the feed to the separator disposed within the drum chamber adjacent the drum axis, for radially inward flow of a specifically lighter component of the feed and radially outward flow of a specifically heavier component, the drum including a discharge passageway for receiving at least part of said specifically heavier component and discharging it from the drum.
 5. Centrifugal separator according to claim 1, the lower side of the drum chamber being defined by the piston valve. 